Blindstitching machine



I Sept. 15, 192s.

' H. l. RAPF'APORT BLINDSTITCHING MACHINE Filed April 29, 1923 ,3 Sheets-Sheet l Sept. 15, 1925. 1,553,717

H. l. RAPPAPORT BLINDSTITCHING MACHINE .Filed April 29, 1923 3 Sheets-Sheet 2 /35 il l/Ill 51101111 loz Sept. 15, 1925.

H. I..RAPPAPORT BLINDSTITCHING MACHINE Filed April 28, 1925 3 Sheets-Sheet 3 ATTORNEY Patented Sept. 15, 1925.`

UNITED STATES PATENT OFFICE.

H'YMAN I. RAPPAPORT, 0F BROOKLYN, NEW YORK, ASSIGNOR. 0F NINETY PER CENT TO JENNIE ROSENTHAL, OF BROOKLYN, NEW YORK.

BLINDSTITCHING MACHINE.

Application led April 28, 1923. Serial' N0. 635,268.

To ZZ whom z't may concern:

Be it known that I, HYMAN I. RAPrAroR'r, a citizen of the United States, and resident of the borough of Brooklyn, citv of New York, in the county of Kings and State of New York, have invented certain new and useful Improvements in a Blindstitching Machine, of which the following is a specification. This invention relates to a blind stitching machine. Its organization is characterized by means to vary the stroke of the feed of the material operated upon. It is further characterized by spring actuated work supl11' ported plates that can slide in vertical planes and simultaneously swing in said planes. The invention contains an oscillating ridge forming head with teeth which pushes forwardly the material operated upon.

The object of the invention is the production of a blind stitchingmachine, in which the length of the stitches" can be varied, by a simple adjustment to vary the lengths of the strokes of the feed dog of the machine.

Fig. 1 represents a side elevation of an exemplication of the blind stitching machine with a section as on the line 1-1 of Fig. 9 and a pair of elements omitted; Fig.

2 shows same details with a section as on the line 2-2 of Fig. 9; Fig. 3 is a top plan view of Fig. 2; Fig. 4 indicates a front elevation of the machine with a section as on the line 4 4 of Fig. 9; Fig. 5 indicates a front elevation of a detail; Fig. 6 is a top plan View of Fig. 5; Fig. 7 shows a front elevation of a detail; Fig. 8 represents a top plan view of Fig. 72 Fig. 9 shows a top plan view of the machlne and Fig. lO'represents an enlarged section on the line 10-10 of Fig. 1.

The main frame of the machine comprises the front member 2O and the rear member 21 connected by the base plate 25 having the projecting lugs 26 and the central opening 27. A body portion 28 of the main frame joins with the rear member 21. Journal lugs 29 and 30 are formed with the front member 20 and journal bearings 314 and 32 are formed lwith the rear member. A front journal bearing 33 with the projecting lug 34 and the rear journal bearing 35 arey formed with the body portion 28. A journal lug 36 extends up from the journal bearing 35 and supports a thread tensioning device 37. A thread guide 38 extends from the bearing 33 and a thread guide 39 extends from the lug 36.

A main driving shaft 40 is journaled in the bearings 31 and 32 and has fastened thereto the usual driving pulley 41 and balance wheel 42.

An adjustable table 45 has formed therewith the journal bearings 46 and 47 at one end, and the cavity 48 at the other end. A shaft 49 is fastened in the lugs 29 and 30, has lhinged thereon the bearings 46 and 47 of the table 45. A hook bolt 50 is indicated with the hook 51 at one end and the threaded portion 52 at the other end. The bolt 50 at one end extends through the front member 20 of the main frame. A helical spring 58 encircles the shaft 49 and one end 59 thereof bears up against the table 45 and its other end 60 is engaged by the hook 51. A nut 61 is provided in the usual wav for the portion 52 of the bolt 50 and the hook 51 engages the end 60 of the spring 58. An arm 62 extends from the table 45. An adjusting screw 63 is in threaded engagement with an opening in the front member 20 of the main frame and one end thereof bears against the arm 62. By means of thel spring 58, the bolt 50 and the screw 63 the table is maintained in requisite tension and position. A lug 64 extends from the lower face of the table 45 and has extending therefrom the operating chain 65.

A supporting bracket is indicated 1n lts entirety by the letter A and comprises the rear vertical wall 66, the vertical wall 67, the upper shelves 68 and the lower shelves 70. The rear vertical wall 66 has its upper end fastened to the table 45 in the cavity 48. A journal bracket 72 extends from the table 45.V A shaft 75 having the crank arm 76 with the crank pin 77 has its ends supported in bearings in the bracket l72 and the wall forming head 82 to oscillate, to form ridges in the material operated upon as will be explained. ,y

An eccentric'90 is fastened to the shaft 40. A bracket 91 is fastened to the frame of the machine at the inner face of the journal bearing 32 and has formed at its upper en the lug 92. 1

A blfurcated lever having the members 94 and 95 is hinged to the lug 92 by means of the screw pivot 96. An adjusting arm 97 with. the arcuate guide opening 98 extends from the member 94. A crank arm 100 is fastened to the shaft 7 5, `A link 101 has one end pivoted to the crank arm 100 by means of the screw pivot 102 and its other end is pivoted to arm 95 by means of the screw pivot 103. When the shaft 40 turns the ec' centric 90, the lever with the members 94 and 95 oscillates on the pivot 96, causing the link 101 to receive a horizontal reciprocating movement resulting in the oscillations of the 4 Yshaft 75.

A lever with the upper arm 108. and the lower arm 109 having the round nose 110 is pivotedto the body portion 28 of the frame of the machine by means of the screw pivot 111. A link 114 is indicated with the heads 115 and 116 and the latter is pinned to the arm 108, by means of the screw pivot 117. The vhead 115 supports the p-in designated in its entirety by the letter B, and comprises the hollow cylindrical portion 118 from which extends the cylindrical portion 119 with the flat side faces 120. The said portions have the interior thread 121. A screw 122 with the head 123y and flange collar 124 enga-ges the thread 121. The head 115 of the link 114 engages the cylindrical portion 118 ofthe pin B and the portion 119Aof said pin is located in the arcuate guide opening 98 of the arm 97. The said 4flattened side faces 12() bear against the adjacent sides of the 'arcuate guide opening 98. A spacer 125 bears between the guide 98 and the flange 124. By means of the screw 122, the pin B can be clamped to the adjusting arm/97 in different positions.

.A feed dog 126is indicated with the usual serrated lower face 127 and extends from an arm 128 formed with the flange 129` An arm is designated in its entirety by the letter C' and comprises the body portion 13() which has formed therein the elongated guide openings 131 and 132. The upper and lower walls of the latter opening are made.

arcuate to allow for the swinging of the arm C as will' be explained. One end of the arm C has formed therewith the extended portion 133 at right angles to the body portion 130 and which has formed therewith the flange 134. The flange 134 has fastened thereto the flange 129 ofthe feed dog 126. An elongated guide opening 135 is formed at one end of the said body portion 130, and an indent 136 28 of the frame of the machine by means of.

the screw pivot 138, which extends'through the guide opening 131 thereof. The nose 110 of the arm 109 engages the indent 136 of the arm C. A pin 139 extends from the body portion 28 and engages the guide opening 135.

An arm is indicated iny its entirety by the letter D and has formed therewith an opening 142 and the bifurcated end with the members 143. A roller 145 is journaled to the ar1n- D. The arm D bears against the arm C and is pivoted on the screw pivot 138 which extends through its opening 142. The roller 145 engages the guide opening 132 of the arm C and the members 143 of the bifurcated end of the arm D engage the eccentric 90. Wheny the shaft 40 rotates the said eccentric 90 causes the arm D to swing on the pin 138 in a vertical plane,` by means of which the feed dog 126 is lightly raised and lowered simultaneously with the oscillations of the shaft 75.

The arm having the members 94 and 95 oscillates .simultaneously with the movements of the arms D and C and consequently the feed dog 126 moves forwardly in'an up er plane, then lowers and moves backwar ly, after which it rises to the upper plane.

The lengths of the reciprocations of the feed dog 126 can be. varied by clamping the pin B inl different positions in the arcuate guide opening 98 of the adjusting arm 97 The longest stroke of the feed dog is obtained when said pin B is located at the upper end of the opening 98. A pair of spring actuated supporting plungers are each designated in their entireties by the letter E. Each of said plungers comprises the cylindrical central portion 150,'that extends into a guidel opening of one of the shelves 70. A threaded shank 151 with .a nut 152 extends from each portion 150. At the upper end ofthe portion is formed a rectangular head 153 that has formed therewith the journal bracket 154. A Work supporting plate 155 is pivoted to each journal bracket 154, by means of the screw pivot 156. Each plate 4155 has formed therewith the4 nose 158 and nal bearings 33 and 35 and has attached to.

its front end the rock arm 164. A curved needle is clamped to the rock arm 164. A supporting plate 168 is fastened to the lug 34 of the journal bearing 33.

.A presser foot 170 has formed therewith the longitudinal guide opening 171 for the feed dog 126 and the ridge forming head 82. A U-shaped bracket 172 extends from the said presser foot. 170 and is fastened to the supporting plate 168 by means of the screws 173. The rear end of the. said presser foot is fastened to the bottom face of the body portion 28 of the main frame of the machine b means of the screw 174.

Connecting means are'provided between the main driving shaft 40 and the rock shaft heads 184 and 185 connects spherical shaped eccentric head 180 and the spherical head 183.

A crank 188 with the crank pin 189 is fastened -to the shaft 40. `An oscillating sleeve-190 with the projecting lug 191 is supported on the crank pin 189. A screw pivot 192 extends from the body portion 28. An oscillating link with the upper sleeve 193 and the lower eccentric strap end 194 is supported on the pivot 192. A connecting rod 195 at one end has fastened thereto the forked shaped member 196 which is pivoted to the lug 191 of the sleeve 190, and a spherical shaped hea-d 197 at its other end is seated in the eccentric strap end 194. A looper 198 is fastened to the forward end of the connecting rod 195 in the usual way.

To operate the blind stitching machine the table is swung down b means of the chain 65, and the folded fabric 200 to be blind stitched is located between the presser foot 170 and the supporting plates 155, after which the chain is released. The tension of the springs 160 tend to lift the plates 155 with the fabric 200 thereon in proper position, so that the teeth of the feed dog 126. can engage said fabric. At the proper times the ridge forming head y 82 bears up against the said fabric, raises it,

forms a ridge thereon and locates said ridge in the guide opening 171 of the presser foot 170, in the path of the -needle 165. The

teeth 85 of the head 82 engage the said fab- Y ric as it swings.

The driving pulley 41 is turned by a belt not shown and thereby the main driving sha-ft 40 is turned, by virtue of which the various moving elements of the machine are moved. to perform their functions and the fabric 200 is fed under the presservfoot 170.

Various modifications may be made in the invention and the present exemplification isto be taken as illustrative and not limitative thereof.

Having described my invention what I desire to secure by Letters Patent and claim 1s:

1. In a blind stitching machine the combination of a frame, a main rotatin driving shaft journaled in the frame, a sli able arm having an elongated guide opening in the machine, a feed dog extending from said arm, a lever pivoted to said frame with one end connected to said arm, an eccentric on the drivin shaft, a lever pivoted to the frame having bifurcated members contacting with said eccentric and having an adjusting arm extending therefrom, a link with one end pivoted to said first lever and the other end adjustably connected to said adjustin arm, a 'second arm in the machine anda pivot supporting the second arm secured to the, frame of the machine and extending through the elongated opening in the first arm, said second arm having a bifurcated end with the members thereof contacting with said eccentric.

2. In a blind stitching machine the combination -of a frame, a main rotating driving shaft journaled in the frame, a slidable arm having a pair of elongated guide openings bearing against said frame, a feed dog extending from said arm, a pivot eXtend ing from the frame extending through one of the guide openings in said arm, a second arm with a bifurcated end bearing against said first arm and supported on said pivot, a roller journaled to the second arm engaging the second elongated opening ofthe first arm, an eccentric on said shaft engaging the bifurcated end of the second arm, a. bifurcated lever pivoted to the frame of the machine with its bifurcated end engaging said eccentric and adjustable means for the said lever to reciprocate said first arm with its feed dog.` j

3. In a blind stitching machine the conibination of a frame, a main rotating driving shaft journaled in the frame an eccentric on said shaft, a slidable arm for the machine, a feed dog extending from said arm, a bifurcated lever pivoted to said frame with its bifurcated end engaging said eccentric, and" adjustable means between said lever and said arm to reciprocate said arm and feed dog with strokes of different lengths. Y

4. 'In a blind stitching machine the combination of a frame, a main rotating driving shaft journaled in the frame, an eccentric on said shaft, a slidable arm in the machine, a feed dog extending from said arm, a bifurcated lever with one end pivoted` to said frame with its bifurcated endengaging said eccentric and having anadjusting arm, a second lever with a pair of arms pivoted to the machine, one of the latter arms connected to said slidable arm and a link connecting the other of said pair of arms and said adjusting arm.

5. In a blind stitching machine the combination of a frame, a main rotating driving shaft journaled in the frame, an `eccentric on said shaft, a slidable arm in the machine, a feed dog extending from the slidable arm, a bifurcated lever with one end pivoted to said frame with its bifurcated end engaging said eccentric and having an adjusting arm with a guide opening, a 'second lever with a pair of arms ivoted to the frame of the machine, one of) the latter arms connected to said slidable arm, a pin extending through said guide opening, means to clamp said pin in different positions in Vsaid guide opening and a link connecting the other one of said pair of arms and said pin.

6. In a blind stitchin machine the combinationof an ad'ustab e table, an oscillating shaft depen ing from said table, a

crank arm with a crank pin extendin from said shaft and a ridge forming head aving a bifurcated leg pivoted to said table, said crank pin engaging said bifurcated leg to oscillate said ridge forming head with the oscillations of said shaft.

7. In a blind stitching machine the combination of an adjustable table, an oscillating shaft depending from said table, a crank arm with a crank pin extending from said shaft, a ridge forming head pivoted in said table and oscillated by said crank arm and pin, a pair of slidable sprin actuated plungers guided in said table an a table pivoted tp each of said plunUers on opposite sides of said ridge forming ead.

8. In a blind stitching machine the combination of a frame, an adjustable table hinged tothe frame, tension and adjusting means for saidtable to maintain it in operative position, an oscillating .shaft depending from said table, a crank arm with ya crank pin extendin from said oscillating shaft and a head wit a ridge and teeth an having a ide opening pivoted in said table,

said cran pin engaging said guide opening.

9., In a blind stitching machine the combination 'of `a frame, an adjustable .table hinged to the frame, tension and adjusting means for said table to maintain it in operative osition, a driving shaft journaled in said rame, a shaft depending from said table, a crank arm` with a crank in extending fromthe latter shaft, means etween the two shafts to oscillate the latter, andy a'ridge forming head having a guide openingpivoted in said table, said crank pin engaging said guide opening. y v

10. In a blind stitching machine the combination of a frame, a driving shaft journaled in the frame, an eccentric for the driving shaft, an adjustable table hinged to the frame, a shaft dependingfrom said table, a ridge forming head ivoted in said table, connections between t e latter shaft and the ridge-forming head, a crank arm extending from the latter shaft, a lever with a bifurcated end pivoted to the frame of the machine, said bifurcated end engaged by the eccentric on the driving shaft and a link connecting said crank arm and said lever having the bifurcated end.

Signed at the borough of Manhattan, cit of New York, in the county of New Yor and State of New York this 10th day of April A. I).'1923.

HYMAN4 I. RAPPAPORT. 

